package org.glow.changgou.filter;

import io.jsonwebtoken.Claims;
import org.glow.changgou.util.JwtUtil;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpCookie;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.net.URL;

/**
 * @Author Glow
 * @Date 2022-10-03 17:59:49
 * @Description JWT过滤规则
 * @Version 1.0
 */
@Component

public class AuthorizeFilter implements GlobalFilter, Ordered {
    //令牌头名字
    private static final String AUTHORIZE_TOKEN = "Authorization";
    //未登录重定向登陆地址
    private static final String USER_LOGIN_URL="http://localhost:9001/oauth/login";
    /***
     * 全局过滤器
     * @param exchange
     * @param chain
     * @return
     */
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        //获取Request、Response对象
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();

        //获取请求的URI
        String path = request.getURI().getPath();
        System.out.println(path);
        //如果是登录、goods等开放的微服务[这里的goods部分开放],则直接放行,这里不做完整演示，完整演示需要设计一套权限系统
        if (URLFilter.hasAuthorize(path)) {
            //放行
            Mono<Void> filter = chain.filter(exchange);
            return filter;
        }

        //获取头文件中的令牌信息
        String tokent = request.getHeaders().getFirst(AUTHORIZE_TOKEN);
        //如果头文件中没有，则从请求参数中获取
        if (StringUtils.isEmpty(tokent)) {
            tokent = request.getQueryParams().getFirst(AUTHORIZE_TOKEN);
        }
        HttpCookie first = request.getCookies().getFirst(AUTHORIZE_TOKEN);
        if (first != null)
        {
            tokent = first.getValue();
        }
        System.out.println(tokent);

        //如果为空，则输出错误代码
        if (StringUtils.isEmpty(tokent)) {
            //设置方法不允许被访问，405错误代码
//            response.setStatusCode(HttpStatus.METHOD_NOT_ALLOWED);
//            return response.setComplete();
            //如果token令牌为空，说明未登录，则需要重定向引导重新登录
            return needAuthorization(USER_LOGIN_URL+"?FROM="+request.getURI(),exchange);
        }

        //解析令牌数据
        try {
//            Claims claims = JwtUtil.parseJWT(tokent);
            //将令牌数据添加到头文件中
//            request.mutate().header(AUTHORIZE_TOKEN,claims.toString());
            request.mutate().header(AUTHORIZE_TOKEN,"Bearer "+tokent);
        } catch (Exception e) {
            e.printStackTrace();
            //解析失败，响应401错误
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }

        //放行
        return chain.filter(exchange);
    }


    /***
     * 过滤器执行顺序
     * @return
     */
    @Override
    public int getOrder() {
        return 0;
    }

    public Mono<Void> needAuthorization(String url,ServerWebExchange exchange)
    {
        ServerHttpResponse response = exchange.getResponse();
        response.setStatusCode(HttpStatus.SEE_OTHER);
        response.getHeaders().set("Location",url);
        return exchange.getResponse().setComplete();
    }
}
